[IAUC] CBET 1879: 20090718 : SUPERNOVA 2009hl

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                                                  Electronic Telegram No. 1879
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
M.S. 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
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SUPERNOVA 2009hl
     Further to CBET 1862, A. J. Drake, S. G. Djorgovski, A. Mahabal, M. J.
Graham and R. Williams, California Institute of Technology; M. Catelan,
Pontificia Universidad Catolica de Chile; E. C. Beshore and S. M. Larson,
Lunar and Planetary Laboratory, University of Arizona; and E. Christensen,
Gemini Observatory, report the CRTS discovery of an apparent supernova in
unfiltered Catalina Sky Survey (CSS) images:

 SN       2009 UT        R.A. (2000.0) Decl.      Mag.      Offset
 2009hl   July 11.40   17 31 10.14  +36 25 40.1   18.0    92".7 W, 52".4 S

Nothing was visible at this position on a CSS image from June 27.31 UT
(limiting mag 20.4).
     J. M. Silverman, M. T. Kandrashoff, and A. V. Filippenko, University of
California, Berkeley, report that inspection of CCD spectra (range 340-1020
nm), obtained on July 16 UT with the 3-m Shane reflector (+ Kast) at Lick
Observatory, shows that 2009hl is a normal type-Ia supernova; after removing
the host-galaxy recession velocity (14824 km/s; Kochanek et al. 2001, Ap.J.
560, 566), the absorption minimum of the Si II 635.5-nm feature is found
to be blue-shifted by about 15700 km/s.  Cross-correlation with a library of
supernova spectra using the "SuperNova IDentification" code (SNID; Blondin a
nd Tonry 2007, Ap.J. 666, 1024) indicates that it is at maximum light.


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                         (C) Copyright 2009 CBAT
2009 July 18                     (CBET 1879)              Daniel W. E. Green